1. Field of the Invention
This invention relates to a solid cast composition containing at least one enzyme or a bacterial spore source capable of in situ generation of at least one enzyme. The products of the invention present a convenient and cost effective method of treating grease traps. For the purposes herein, a grease trap is considered to be the grease trap and the drain lines leading to the grease trap.
2. Background
A common problem in the treatment of waste water is the presence of oleo components, particularly triglycerides (commonly referred to as grease). The difficulty encountered in handling these oleo components is a concern to the food industry and to the operators of municipal sewage treatment systems. The food industry referred to herein is that which prepares cooked food where grease is generated. The food industry includes establishments such as restaurants, hospitals, and other commercial food processors.
The food industry recovers and recycles the oleo components from the cooking process. However, a substantial portion of the oleo components in the waste water from washing dishes, cooking vessels, and flatware enters the sewage system.
The first step in most sewage systems is a grease trap and the sewer drain lines leading to the grease trap which are maintained by the food processor. Typically, the grease trap is constructed to permit water containing effluent from the food processor to separate into a largely aqueous phase and an oleo phase. The aqueous phase containing some oleo components is permitted to pass into a municipal sewage treatment system.
The municipal sewage treatment system comprises the pipes leading to a sewage treatment plant and the sewage treatment plant. The pipes leading to the sewage treatment plant may be constricted because of grease build up. The sewage treatment plant is often of limited capacity in the amount of sewage that may be treated and in the type of treatment that may be given to the plant influent.
The collection of grease from a grease trap creates problems for the food processor in grease removal and also produces objectionable odors. Thus, grease removal is preferably done at a time when the customers of food processor are not present. The municipal sewage treatment system officials do not want the sewage pipes to become constricted from the grease. Preferably, the municipal sewage treatment system officials want the grease contained in the grease trap of the food processor.
It is also preferred by the municipal sewage treatment officials that the grease trap treatment by the fond processor be confined to the grease trap. The latter preference is to avoid large amounts of enzymes from entering the sewage pipes. Large amounts of enzymes may act on the grease on the inner walls of the sewage pipes thereby releasing clumps of grease to the municipal sewage treatment system. The result, when clumps of grease are released to the municipal sewage treatment system, is that the municipal sewage treatment system is overwhelmed and untreated effluent may result unless costly corrective steps are taken.
Conventional methods of treating grease traps involve the addition of enzymes or bacterial spores to the grease trap such as via a drain or the drain lines. The method of addition of the enzymes or bacterial spores to the grease trap is typically by a liquid product or by a powdered mixture of an enzyme or bacterial spore and sawdust.
The product is usually introduced to the grease trap by an employee, often an employee with no specific training in the treatment of grease traps. Thus, the potential for overtreating, undertreating, or not treating the grease trap at the appropriate--time interval exists.
Overtreatment of the grease trap may result in the enzyme reaching the sewage pipes, while undertreatment and delayed treatment may result in the grease escaping the grease trap and entering the sewage pipe. If a liquid treatment is employed it may be ineffective as the bacterial spores and enzymes settle to the bottom of container in which the liquid product is stored. Pouring doses of the enzyme and/or bacterial spores from a non-homogeneous liquid introduces widely varying amounts of the active ingredients.
Powdered products, such as where the enzymes or spores are deposited on sawdust, may result in uneven dosing of the grease trap. Powdered products are also prone to spillage and handling problems.
Conventional methods of treating a grease effluent, as discussed above, include the use of grease traps as discussed in U.S. Pat. No. 5,507,954, issued to Carrillo on Apr. 16, 1996. Further disclosures of methods of treating a grease trap are found in U.S. Pat. No. 5,225,085, issued on Jul. 6, 1993 to Napier et al.
A general discussion of bacterial spores is found in SPOREZYME BCC published by Semco Laboratories, Inc. of Milwaukee, Wis. A device for the use of bacterial cultures to assist in biodegrading waste is found in U.S. Pat. No. 4,810,385, issued on Mar. 7, 1989 to Hater et al.
The reader is also directed to U.S. Pat. No. 5,348,653, issued on Sep. 20, 1994 to Rovel, which discusses the biological purification of effluent. Wong et al., in U.S. Pat. No. 4,882,059, issued on Nov. 21, 1989, discuss solubilizing organic materials in waste water. U.S. Pat. No. 5,464,766 to Bruno, issued Nov. 7, 1995 discusses the use of powdered enzymes for effluent treatment.
The construction of grease traps is disclosed in U.S. Pat. No. 4,940,539, issued Jul. 10, 1990 to Weber. A further discussion of grease trap construction is found in Pappas et al., U.S. Pat. No. 4,225,083, issued Jul. 6, 1993.
To the extent that the references discussed herein are applicable to the present invention they are herein specifically incorporated by reference. Temperatures given herein are degrees Celsius unless otherwise indicated. Throughout the specification and claims, percentages and ratios are by weight unless otherwise indicated. Percentages are based upon the combined weight of the components recited in the pertinent claims. Ranges and ratios given herein may be combined.